A printer configured to discharge liquid droplets of ink or the like onto a sheet and to form dots for printing has been known. The printer is configured to convey the sheet from an upstream side toward a downstream side with holding the sheet by using a roller disposed at a more upstream side than a printing head and a roller disposed at a more downstream side than the printing head, for example. In this case, a printing on a central part in a conveying direction of the sheet is executed with the sheet being held by both the rollers. Incidentally, a printing adjacent to a sheet end, for example, a downstream end or an upstream end is executed at a state where the sheet is held by one roller and is not held by the other roller.
At the state where the sheet is held only by one roller, the sheet is more likely to be deformed, depending on the gravity, types of the sheet, mounting environments of the printer and the like, as compared to a state where the sheet is held by both the rollers. The deformation of the sheet may vary a gap between the printing head and the sheet and cause the sheet and the printing head to contact each other. For this reason, deterioration of a printing quality such as positional deviation of the dots and smudge of the sheet may be caused due to the deformation of the sheet.
There has been disclosed a technology of contriving a conveying amount of the sheet to shorten a distance from a position on the sheet held by one roller to an end of the sheet when the printing is executed with the sheet being held only by one roller. According to the related-art technology, it is possible to suppress the deterioration of the printing quality by suppressing the deformation of the sheet.